Easily the most pathetic revelation from Gillian Duffy's interview in the Mail on Sunday was her description of Gordon Brown's palpable longing for his wife's soothing presence when he went miserably crawling back to the now-famous house in Rochdale.

"He spoke a lot about Sarah. He said she was a good woman," reported Mrs Duffy. He told her: "If you ever come down [to London], you must come to No 10 and meet me and Sarah."

"You went and met people last week with unfortunate results," began Lorraine Kelly – and Gordon jumped in a little too eagerly: "Sarah wasn't there then – ha ha!" he hooted, reaching for his wife's hand. Sarah did not laugh.

"If you'd been there would that have happened?" asked Lorraine.

"I wasn't there so I really don't know one way or the other," she replied, which is former PR-wife-speak for "Obviously."

"Was it Sarah you called right away?" Lorraine asked, turning back to Gordon.

"This is very personal but …" began Gordon. Come on, man, this is GMTV! This is what you're here for, stop trying to talk about tax credits. He soon acquiesced: "[When I] make a mistake – talk to Sarah," he replied, sounding like a young boy reciting his parents' rules about how to cross the road. But even this was wrong, and Sarah stepped in: "We always talk to each other when things happen," she said, with the euphemism of a trained PR.

"I'm impatient, Sarah's better organised than me ..."

"Well – better organised AT HOME," Sarah quickly inserted, pretty much looking straight into the camera, foreseeing, no doubt, some dodgy headlines about Gordon being a mess of a PM.

And my goodness, he is so grateful to her! He's like the school nerd who can't believe he finally has a girlfriend. Perfect Sarah, PR-queen Sarah, nothing bad ever happens if Sarah's around.

Sarah affects disinterest in her media critics. Gordon, however, answered a very firm "yes" when Lorraine asked if he gets angry when people criticise his wife's appearance. "I just think she does such a good job campaigning me, supporting me …" and at this point a smile broke out, as if he still couldn't believe his luck.

There was, at first, no hand-holding, no limb-crossing, whereas you can be sure that if the Camerons had been on the sofa there would have been full-on bump patting from the get-go. Instead, just Gordon sitting in his usual hunch, Sarah, blow-dryed and calm, sitting straight up.

Interestingly, Gordon – reeking of desperation – was the one who was more willing to discuss the personal. When Lorraine broached the subject of their children (a far more private topic for them than it has been for the Camerons), Gordon was full of comedy details: that they're more interested in Legoland, how sweet they are, etc. Sarah, perhaps sensing that at this stage there's not even any ground to be gained from showcasing the kids, could barely be persuaded to admit that she phones them from the campaign trail.

"You look very protective of your husband," Lorraine mused. Yes, Lorraine, and the sky is blue.

Gordon looked quite pleased by this analysis. Sarah – not so.

"It's more that I don't want to be left behind from him. But together we're getting through the crowds," she replied.